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Commutator lifting inequalities and interpolation

Gelu Popescu
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Abstract

In this paper we obtain a multivariable commutator lifting inequality, which extends to several variables a recent result of Foias, Frazho, and Kaashoek. The inequality yields a multivariable lifting theorem generalizing the noncommutative commutant lifting theorem. This is used to solve new operator-valued interpolation problems of Schur-Caratheodory, Nevanlinna-Pick, and Sarason type on Fock spaces. Some consequences to norm constrained analytic interpolation in the unit ball of C^n are also considered.

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Gelu Popescu. 2003-10-06. Commutator lifting inequalities and interpolation. https://arxiv.org/abs/math/0310081

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